Php 解析错误mysql 2变量

我的密码是

$newentry = "
    UPDATE url 
    FROM auction_media 
    JOIN auctions ON auction_media.auction_id = auctions.auction_id                                            
    SET media_url = '$row2['url']/$match[0]' 
    WHERE media_type =  '3'";

我得到的错误是

---

分析错误：语法错误，意外的T_封装的_和_空格，需要T_字符串或T_变量或T_NUM_字符串

此代码段似乎有误：

$newentry = "UPDATE `url` FROM `auction_media` JOIN `auctions` ON `auction_media.auction_id` = `auctions.auction_id` SET `media_url` = '".$row2['url']."/".$match[0]."' WHERE `media_type` =  '3'";

SET media_url = '$row2['url']/$match[0]'

更正如下：

SET media_url = '" . $row2['url'] . "/" . $match[0] . "'

请尝试以下方法：

 $newentry = "UPDATE url FROM auction_media JOIN auctions ON auction_media.auction_id = auctions.auction_id SET media_url = '" . $row2['url'] . "/" . $match[0] . "' WHERE media_type =  '3'";

---

这段代码似乎是错误的：

SET media_url = '$row2['url']/$match[0]'

更正如下：

SET media_url = '" . $row2['url'] . "/" . $match[0] . "'

请尝试以下方法：

 $newentry = "UPDATE url FROM auction_media JOIN auctions ON auction_media.auction_id = auctions.auction_id SET media_url = '" . $row2['url'] . "/" . $match[0] . "' WHERE media_type =  '3'";

---

假设该查询将实际工作：

$newentry = "UPDATE url
    FROM auction_media
    JOIN auctions
        ON auction_media.auction_id = auctions.auction_id
    SET media_url = '" . $row2['url'] . '/' . $match[0] . "'
    WHERE media_type =  '3'";

---

假设该查询将实际工作：

$newentry = "UPDATE url
    FROM auction_media
    JOIN auctions
        ON auction_media.auction_id = auctions.auction_id
    SET media_url = '" . $row2['url'] . '/' . $match[0] . "'
    WHERE media_type =  '3'";